Skip Navigation LinksHome > Published Ahead-of-Print > Mesenchymal Stem Cells Augment the Adaptive Response to Ecce...
Medicine & Science in Sports & Exercise:
doi: 10.1249/MSS.0000000000000405
Original Investigation: PDF Only

Mesenchymal Stem Cells Augment the Adaptive Response to Eccentric Exercise.

Zou, Kai; Huntsman, Heather D.; Valero, M. Carmen; Adams, Joseph; Skelton, Jack; De Lisio, Michael; Jensen, Tor; Boppart, Marni D.

Published Ahead-of-Print
Collapse Box


Purpose: The [alpha]7[beta]1 integrin is a transmembrane protein expressed in skeletal muscle that can link the actin cytoskeleton to the surrounding basal lamina. We have previously demonstrated that transgenic mice overexpressing the [alpha]7B integrin in skeletal muscle (MCK:[alpha]7B; [alpha]7Tg) mount an enhanced satellite cell and growth response to single or multiple bouts of eccentric exercise. Additionally, interstitial stem cells characterized as mesenchymal stem cells (MSCs) accumulate in [alpha]7Tg muscle (mMSCs) in the sedentary state and post-exercise. The results from these studies prompted us to determine the extent to which mMSCs underlie the beneficial adaptive responses observed in [alpha]7Tg skeletal muscle post-exercise.

Methods: mMSCs (Sca-1+CD45-) were isolated from [alpha]7Tg mice, dye-labeled, and intramuscularly injected into adult wild type recipient mice. Following injection of mMSCs or saline, mice remained sedentary (SED) or were subjected to eccentric exercise training (TR) (downhill running) on a treadmill (3X/week) for two or four weeks. Gastrocnemius-soleus complexes were collected 24 hours after the last bout of exercise.

Results: mMSCs did not directly fuse with existing fibers, however, mMSC injection enhanced Pax7+ satellite cell number and myonuclear content compared to all other groups at two weeks post-exercise. Mean CSA, percentage of larger caliber fibers (>3000 [mu]m2) and grip strength were increased in mMSC/TR compared to Saline/SED and mMSC/SED at four weeks. mMSC transplantation did not enhance repair or growth in the absence of exercise.

Conclusion: The results from this study demonstrate that mMSCs contribute to beneficial changes in satellite cell expansion and growth in [alpha]7Tg muscle following eccentric exercise. Thus, MSCs that naturally accumulate in muscle following eccentric contractions may enhance the adaptive response to exercise.

(C) 2014 American College of Sports Medicine


Article Tools


Search for Similar Articles
You may search for similar articles that contain these same keywords or you may modify the keyword list to augment your search.

Connect With Us